The Regional Wastewater Reclamation Department (RWRD) is responsible for leading a major sewer improvement effort that involves three distinct and inter-related projects. These three projects, to be constructed or upgraded in the next 36 months, represent a $41 million investment that will extend the life cycle of our community’s wastewater facilities by 50+ years.
The North Rillito Interceptor (NRI) project is approximately 10 miles long. The NRI is a large diameter pipeline that transports wastewater from the City’s far east side in the Woodland Road and Bear Canyon area, along the north bank of the Tanque Verde Creek and Rillito River, to the Ina Road Wastewater Treatment Facility -- which serves a major portion of northern and eastern Tucson. Although there are no immediate plans to increase the NRI’s capacity due to limited density growth, the RWRD must comply with U.S. E.P.A. guidelines relating to wastewater system capacity, management, operations and maintenance and to minimizing the number of sewer overflows.
The RWRD’s South Rillito Interceptor (SRI) is another major interceptor with additional capacity that runs along the south side of the Rillito River, parallel to the NRI. The SRI rehabilitation project begins in an area near Columbus Boulevard and runs west for 3.9 mile along the south bank of the Rillito River to the intersection of Roger Road and Tucson Blvd.
The North Rillito Interceptor Relief project will connect the NRI and the SRI in the Columbus Boulevard area. Ultimately this new connection allows the RWRD to convey 10 million gallons of wastewater a day, reducing the potential for sewer overflows and ensuring compliance with U.S.E.P.A. guidelines for capacity, management, operations and maintenance.
Construction of the new NRI Relief facilities requires heavy civil work related to excavation required for structures and the sewer siphon from the north bank to the south bank of the Rillito River.